Should I update to OS X Mavericks?

I am using an early 2010 Macbook Pro, still running Snow Leopard because I never had any reason to update to Lion or Mountain Lion and didn’t know if I should. Here are my specs:

Version 10.6.8
Model Name: MacBook Pro
Model Identifier: MacBookPro5,4
Processor Name: Intel Core 2 Duo
Processor Speed: 2.53 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 3 MB
Memory: 4 GB
Bus Speed: 1.07 GHz
Boot ROM Version: MBP53.00AC.B03
SMC Version (system): 1.49f2

Why I’m thinking about upgrading now is that I have just started a new job and will be using Eclipse running Python. These are installed on the work computers and I don’t technically need them on my own computer but since I’m completely new at this I wanted to come home and practice too. I downloaded both Eclipse and Python but when looking at installation instructions apparently I need to have Java 7 installed for PyDev to work in Eclipse. Or something. I really have no idea about all this stuff. But apparently Java 7 is only for OS X 10.7 and later?

So I’m looking at Lion and Mountain Lion, at $25 each, when I realise that 10.9 Mavericks is available free.

My question is- is it worth me downloading Mavericks or should I baby step it to Lion first? I’d rather not have to pay $25 but if Mavericks is not going to run properly on my computer now that it’s a few years old I don’t want to go down that road either. I’m in Germany far from my home country of Australia and don’t want to have to take my laptop into somewhere if something goes wrong since I can’t actually speak German and of course it’s not in warranty. I don’t want anything to go wrong in the first place either because I don’t want to be cut off from communication to my family and university back home and stuff.

I might be paranoid about this but I am really technologically handicapped and I am not sure what to do. Should I even update at all? Will Lion also be too much for my poor old lady? She is going pretty strong though, just the battery life of course not what it used to be.

Please help!

Edit :: Crap. I just realised I didn’t bring my time machine/back up hard drive with me to Germany… I do have another hard drive with me though, is it possible to do a one time system back up on to a different hard drive without partitioning it into a time machine? How do I check how much space I would need?

Also don’t know if this makes a difference but the most cleaned up my laptop gets these days leaves me with about 50GB of space. I think all the updates need 8 each.